package com.dev.jaye.code.source.lang;

/**
 * @author Dev_J
 * @date 2021-04-29 15:59
 */
public class SystemLearn {
    public static void main(String[] args) {
        System.out.println("系统自带");
    /**
     * 飘红报错主要是没有直接调用建议直接调用
     */
        SystemOut.out.println("xxxxx");
        //建议
        PrintStreamLearn.println("xxxxx");
    }

}
class SystemOut{
    public final static PrintStreamLearn out = null;
}

/**
 * 必须要带static否则会空指针异常
 */
class PrintStreamLearn{
    public static void println(String x) {
        System.out.println(x);
    }
}
/**
 * 参考文章--> https://blog.csdn.net/yldmkx/article/details/108937190
 */